Role of Ku70 in the Apoptosis of Inflamed Dental Pulp Stem Cells

Overview

Journal Inflamm Res

Specialties Allergy & Immunology
Pathology

Date 2018 Jul 16

PMID 30008029

Citations 4

Authors

Yequan Huang

Weiwei Qiao

Xinhuan Wang

Qian Gao

Yao Peng

Zhuan Bian

Liuyan Meng

Affiliations

Soon will be listed here.

Abstract

Aim: The study aimed to investigate the effects of DNA repair proteins on cell apoptosis in human DPSCs during inflammation.

Methods: Lipopolysaccharide (LPS) was used to stimulate inflammation in dental pulp in vivo and in vitro. We identified the activation of DSB response and DNA repair proteins in inflamed pulp tissue and in LPS-treated human DPSCs. Then we transfected the cells with Ku70 (a key protein involved in NHEJ) siRNA and detected the expression changes of γ-H2A.X, DNA repair proteins and cell apoptosis.

Results: Immunohistochemical staining showed that at 4 and 6 days of pulpitis the expression of Ku70 and γ-H2A.X significantly increased. The levels of γ-H2A.X, Ku70, Xrcc4, and Rad51 increased considerably in the LPS-treated DPSCs. Furthermore, decreased expression of Ku70 could increase the number of γ-H2A.X foci, apoptotic cells and reduce cell viability in DPSCs.

Conclusions: The results indicate that NHEJ pathway was the main mechanism involved in DNA damage response induced by repeated LPS stimulation in DPSCs. Meanwhile, the findings suggested that Ku70 serves importantly in the apoptosis of DPSCs in the inflammatory environment.

Citing Articles

Therapeutic Potential of Synthetic Human -Defensin 1 Short Motif Pep-B on Lipopolysaccharide-Stimulated Human Dental Pulp Stem Cells.

Shi J, Hu Z, Zhou Y, Zuo M, Wu H, Jin W Mediators Inflamm. 2022; 2022:6141967.

PMID: 35110972 PMC: 8803462. DOI: 10.1155/2022/6141967.

Role of Lipopolysaccharide, Derived from Various Bacterial Species, in Pulpitis-A Systematic Review.

Brodzikowska A, Ciechanowska M, Kopka M, Stachura A, Wlodarski P Biomolecules. 2022; 12(1).

PMID: 35053286 PMC: 8774278. DOI: 10.3390/biom12010138.

Microenvironment Influences Odontogenic Mesenchymal Stem Cells Mediated Dental Pulp Regeneration.

Huang X, Li Z, Liu A, Liu X, Guo H, Wu M Front Physiol. 2021; 12:656588.

PMID: 33967826 PMC: 8100342. DOI: 10.3389/fphys.2021.656588.

DNA repair fidelity in stem cell maintenance, health, and disease.

Mani C, Reddy P, Palle K Biochim Biophys Acta Mol Basis Dis. 2019; 1866(4):165444.

PMID: 30953688 PMC: 6935429. DOI: 10.1016/j.bbadis.2019.03.017.

References

Savina N, Smal M, Kuzhir T, Ershova-Pavlova A, Goncharova R . DNA-damage response associated with occupational exposure, age and chronic inflammation in workers in the automotive industry. Mutat Res. 2012; 748(1-2):21-8. DOI: 10.1016/j.mrgentox.2012.06.006. View

Cooper P, Holder M, Smith A . Inflammation and regeneration in the dentin-pulp complex: a double-edged sword. J Endod. 2014; 40(4 Suppl):S46-51. DOI: 10.1016/j.joen.2014.01.021. View

Wang X, Zhu J, Fang Y, Bian Z, Meng L . Lower concentrations of receptor for advanced glycation end products and epiregulin in amniotic fluid correlate to chemically induced cleft palate in mice. Environ Toxicol Pharmacol. 2017; 51:45-50. DOI: 10.1016/j.etap.2017.02.025. View

Wang M, Hung P, Tu H, Shih W, Li W, Chang K . Lipopolysaccharide induces the migration of human dental pulp cells by up-regulating miR-146a. J Endod. 2012; 38(12):1598-603. DOI: 10.1016/j.joen.2012.09.008. View

Hu J, Meyers R, Dong J, Panchakshari R, Alt F, Frock R . Detecting DNA double-stranded breaks in mammalian genomes by linear amplification-mediated high-throughput genome-wide translocation sequencing. Nat Protoc. 2016; 11(5):853-71. PMC: 4895203. DOI: 10.1038/nprot.2016.043. View

Nagasawa H, Brogan J, Peng Y, Little J, Bedford J . Some unsolved problems and unresolved issues in radiation cytogenetics: a review and new data on roles of homologous recombination and non-homologous end joining. Mutat Res. 2010; 701(1):12-22. DOI: 10.1016/j.mrgentox.2010.03.003. View

Burguillos M, Hajji N, Englund E, Persson A, Cenci A, Machado A . Apoptosis-inducing factor mediates dopaminergic cell death in response to LPS-induced inflammatory stimulus: evidence in Parkinson's disease patients. Neurobiol Dis. 2010; 41(1):177-88. DOI: 10.1016/j.nbd.2010.09.005. View

Xie H, Wise S, Holmes A, Xu B, Wakeman T, Pelsue S . Carcinogenic lead chromate induces DNA double-strand breaks in human lung cells. Mutat Res. 2005; 586(2):160-72. PMC: 4136752. DOI: 10.1016/j.mrgentox.2005.06.002. View

Wang X, Sha X, Li G, Yang F, Ji K, Wen L . Comparative characterization of stem cells from human exfoliated deciduous teeth and dental pulp stem cells. Arch Oral Biol. 2012; 57(9):1231-40. DOI: 10.1016/j.archoralbio.2012.02.014. View

10.

Faure V, Wenner T, Cooley C, Bourke E, Farr C, Takeda S . Ku70 prevents genome instability resulting from heterozygosity of the telomerase RNA component in a vertebrate tumour line. DNA Repair (Amst). 2008; 7(5):713-24. DOI: 10.1016/j.dnarep.2008.01.008. View

11.

Botero T, Son J, Vodopyanov D, Hasegawa M, Shelburne C, Nor J . MAPK signaling is required for LPS-induced VEGF in pulp stem cells. J Dent Res. 2010; 89(3):264-9. DOI: 10.1177/0022034509357556. View

12.

Liu C, Lo J, Kuo C, Chu C, Chen L, Tsai F . Akt mediates 17beta-estradiol and/or estrogen receptor-alpha inhibition of LPS-induced tumor necresis factor-alpha expression and myocardial cell apoptosis by suppressing the JNK1/2-NFkappaB pathway. J Cell Mol Med. 2010; 13(9B):3655-67. PMC: 4516514. DOI: 10.1111/j.1582-4934.2009.00669.x. View

13.

Stingele J, Schwarz M, Bloemeke N, Wolf P, Jentsch S . A DNA-dependent protease involved in DNA-protein crosslink repair. Cell. 2014; 158(2):327-338. DOI: 10.1016/j.cell.2014.04.053. View

14.

Yu G, Kubota H, Okita M, Maeda T . The anti-inflammatory and antioxidant effects of melatonin on LPS-stimulated bovine mammary epithelial cells. PLoS One. 2017; 12(5):e0178525. PMC: 5444821. DOI: 10.1371/journal.pone.0178525. View

15.

Lieber M, Ma Y, Pannicke U, Schwarz K . Mechanism and regulation of human non-homologous DNA end-joining. Nat Rev Mol Cell Biol. 2003; 4(9):712-20. DOI: 10.1038/nrm1202. View

16.

Feng X, Feng G, Xing J, Shen B, Tan W, Huang D . Repeated lipopolysaccharide stimulation promotes cellular senescence in human dental pulp stem cells (DPSCs). Cell Tissue Res. 2014; 356(2):369-80. DOI: 10.1007/s00441-014-1799-7. View

17.

Subramanian C, Jarzembowski J, Opipari Jr A, Castle V, Kwok R . HDAC6 deacetylates Ku70 and regulates Ku70-Bax binding in neuroblastoma. Neoplasia. 2011; 13(8):726-34. PMC: 3156663. DOI: 10.1593/neo.11558. View

18.

Mari P, Florea B, Persengiev S, Verkaik N, Bruggenwirth H, Modesti M . Dynamic assembly of end-joining complexes requires interaction between Ku70/80 and XRCC4. Proc Natl Acad Sci U S A. 2006; 103(49):18597-602. PMC: 1693708. DOI: 10.1073/pnas.0609061103. View

19.

Stockert J, Blazquez-Castro A, Canete M, Horobin R, Villanueva A . MTT assay for cell viability: Intracellular localization of the formazan product is in lipid droplets. Acta Histochem. 2012; 114(8):785-96. DOI: 10.1016/j.acthis.2012.01.006. View

20.

Ferguson L . Chronic inflammation and mutagenesis. Mutat Res. 2010; 690(1-2):3-11. DOI: 10.1016/j.mrfmmm.2010.03.007. View